Place the white chocolate morsels into a microwave-safe bowl and heat in the microwave about 2 minutes, stirring every 15 seconds, until completely melted. Add in a few drops of green food coloring and stir. If your white chocolate becomes too thick, add just a drop of vegetable oil or melted coconut oil.
Add a heaping tablespoon of melted white chocolate into molds. Spread using the back of the spoon until each cavity is completely covered.
Place in the refrigerator and let set for about 15 minutes.
Remove molds from refrigerator, and press gently on the top of each sphere to carefully remove onto a baking sheet.
Fill 6 spheres with a tablespoon of hot chocolate mix and couple of tablespoons of mini marshmallows, each.
Warm a skillet or plate, and place the bottom of an empty sphere on the plate to lightly melt chocolate. Place melted chocolate edge on top of the filled half to seal.
To decorate: melt some additional white chocolate morsels and drizzle it onto the hot chocolate bombs. Add a few holiday sprinkles on top of each hot chocolate bomb.
Refrigerate until ready to serve.